Invalid conversion c++ - c++

Question

I get this error
invalid conversion from 'GameObject*' to 'std::vector::value_type {aka SDLGameObject*}' [-fpermissive]
This is my code I don't know what is wrong because in my class MainMenu it works this is my class Playstate.cpp
bool PlayState::onEnter()
{
SDL_ShowCursor(1);
//parse the state
TheTextureManager::Instance()->load("assets/button.png", "test", TheGame::Instance()->getRenderer());
GameObject* pGameObject1 = TheGameObjectFactory::Instance()->create("MenuButton");
pGameObject1->load(new LoaderParams(120, 300, 400, 100, "test", 4, 4, 4));
m_gameObjects.push_back(pGameObject1);
}
GameObject.h
#include "LoaderParams.h"
#include <string>
using namespace std;
class GameObject {
public:
virtual void draw() = 0;
virtual void update() = 0;
virtual void clean() = 0;
virtual void load(const LoaderParams* pParams)=0;
protected:
GameObject() {}
virtual ~GameObject() {}
};
#endif /* GAMEOBJECT_H_ */
SDLGameObject.h
#ifndef SDLGAMEOBJECT_H_
#define SDLGAMEOBJECT_H_
#pragma once
#include "GameObject.h"
#include "LoaderParams.h"
#include "TextureManager.h"
#include "Vector2D.h"
class SDLGameObject : public GameObject {
public:
SDLGameObject();
virtual void draw();
virtual void update();
virtual void clean(){}
virtual void load(const LoaderParams* pParams);
Vector2D& getPosition() { return m_position; }
virtual int getWidth() { return m_width; }
virtual int getHeight() { return m_height; }
protected:
Vector2D m_position;
Vector2D m_velocity;
Vector2D m_acceleration;
int m_width;
int m_height;
int m_currentRow;
int m_currentFrame;
std::string m_textureID;
};
#endif /* SDLGAMEOBJECT_H_ */
MainMenuState.cpp here it does work!!
bool MainMenuState::onEnter()
{
SDL_ShowCursor(1);
//parse the state
TheTextureManager::Instance()->load("assets/button.png", "playbutton" , TheGame::Instance()->getRenderer());
TheTextureManager::Instance()->load("assets/exit.png", "exitbutton" , TheGame::Instance()->getRenderer());
GameObject* pGameObject = TheGameObjectFactory::Instance()->create("MenuButton");
GameObject* pGameObject1 = TheGameObjectFactory::Instance()->create("MenuButton");
pGameObject->load(new LoaderParams(120, 150, 400, 100, "playbutton", 0, 1, 2));
pGameObject1->load(new LoaderParams(120, 300, 400, 100, "exitbutton", 1, 2, 2));
m_gameObjects.push_back(pGameObject);
m_gameObjects.push_back(pGameObject1);
m_callbacks.push_back(0);
m_callbacks.push_back(s_menuToPlay);
m_callbacks.push_back(s_exitFromMenu);
//set callbacks for menu items
setCallbacks(m_callbacks);
std::cout << "Entering MainMenuState\n";
return true;
}

Answer 1

SDLGameObject derives from the base class GameObject. Your vector m_gameObjects stores pointers to SDLGameObject, but you are giving it a pointer to a GameObject.
This conversion is not possible as a GameObject is not necessarily an SDLGameObject.
If you are sure that this is the case you can do this:
SDLGameObject* p = dynamic_cast<SDLGameObject>(pGameObject1);
if(!p) {
// pGameObject1 is actually not an SDLGameObject
}
m_gameObjects.push_back(p);
Or change the definition of m_gameObjects to store pointers to GameObject.